Turbines utilize vanes that extend into the turbine cavity to direct the air as the air flows through the turbine. These vanes must be cooled in order for them to sustain the high temperatures within the turbine environment. The turbine vane assembly, which incorporates the vanes, is constructed to allow cooling fluid, e.g., air, to permeate in, along, and around the vane.
Part of the turbine vane assembly includes a pressurized cavity into which air is forced to facilitate the cooling action mentioned above. A cover plate is implemented as part of this assembly, the cover plate being so constructed to maintain pressure in the cavity as well as to permit air to impinge on various parts of the vane. The cover plate is mounted to portions of the vane assembly that may include cast parts and surfaces onto which the cover plate must seal to maintain pressure in the pressurized cavity.
Some of these portions may have multiple levels that form a well or depression. The cover plate must therefore be designed to not only fit into the well, but also to seal to the surfaces at each of the multiple levels.